题干

东营市北临渤海,海岸线全长412.67公里.渤海以其博大辽阔孕育了丰富的动物资源,其中,浮游动物100多种,底栖动物140多种,游泳动物120余种,代表种类有水母、黄海葵、三疣梭子蟹、泥螺、毛钳、沙蚕、文蛤、褶牡蛎、中国对虾、脊尾白虾、黄鲫鱼、鲈鱼、海豚等.请分析回答:

(1)动物学家通常将以上动物分成两大类,其分类的主要依据是____ .

(2)水母、黄海葵属于腔肠动物,它们身体呈圆筒状,体壁由____ 组成.

(3)文蛤身体柔软,以水中的微小生物为食,其运动器官为____ .

(4)中华对虾、三疣梭子蟹的共同特征是身体分部、____ ,体表有外骨骼.

(5)鲈鱼为温水性近海中下层鱼类,用____ 呼吸,常结成小群活动.

(6)海豚是聪明伶俐的海洋哺乳动物,已被有关国家调练成海豚兵,能够识别、侦查、摧毁敌方战舰,这属于____ 行为.

(7)人们对渤海生物资源的过度开发利用,已对海洋生物多样性造成破坏,保护生物多样性,首先要保护____ ,保护生态系统的多样性.

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体内有无脊柱,内胚层、外胚层和中胶层,斧足,触角和足也分节,鳃,学习,栖息地

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Several days ago,Brenda had a car accident.As a result.one of her legs had to be cut off.She became quiet and didn't talk to anyone.

    "I wish I could bring her friends to visit her," Brenda's mother said to the nurse."It's just too long a bus trip.""Don't worry," the nurse smiled."I have a plan."

    Later that day, the nurse told Brenda it was moving day.Before Brenda could refuse,the nurse had taken her to another room filled with colourful flowers."Here's your new roommate,Annie,"the nurse told a dark-haired teenager(青少年)on the other bed.

    Annie smiled.After the nurse left.she hopped (单脚跳)out of her bed and sat at the other end of Brenda's.

    "I lost one of my legs from bone cancer (骨癌),"she said."What happened to yours?"Brenda was so surprised that she couldn't say a word."You're  ▲  ."Annie continued."You've still got your knee.They had to take mine."

    Annie hopped back to her bed."l'd like to talk with you,but my friends are coming any time now,so I have to get ready," Annie said when she reached up and took off her hair!Her head was completely bald(秃的).

"Oh,I forgot to tell you,the medicine they gave me to kill(杀死) the cancer also killed my hair,"Annie said.

    When Annie's friends came.she introduced Brenda to them all.Before long,Brenda started talking with Annie and her friends.They didn't make her feel like a freak (怪人) at all!By the time the nurse asked·the visitors to leave.Brenda feIt great.

    The girls talked into the night and shared their dreams with each other.When it was time to go to bed,Brenda said,"Good night,Annie.Can't wait till morning."

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